1. Field of the Invention
This invention relates to an optical connector connected to ends of photoconductive members, such as optical fibers, so as to connect optical transmission circuits together.
2. Prior Art
FIG. 7 shows one known conventional optical connector.
In this Figure, the optical connector 1 comprises optical connector plugs 2 and 2, a ferrule holder 3, and a connector housing 4.
Each of the optical connector plugs 2 and 2 comprises a photoconductive member 5 (e.g. optical fiber), and a cylindrical ferrule 6 having a smaller-diameter portion 6a and a larger-diameter portion 6b. A conductor portion (not shown) of each of the photoconductive members 5 and 5 is received in the smaller-diameter portion 6a, and a sheath 5a thereof is received in the larger-diameter portion 6b.
The ferrule holder 3 includes a box-like housing 7, having a front end surface part of which is open for the optical connector plugs 2, and a support wall 8 of an oval cross-section formed integrally on a rear end surface of the housing 7. A recess 7b is formed in a central portion of an upper wall 7a of the housing 7, and rectangular retaining holes 7c and 7c are formed in this upper wall 7a, and are disposed respectively on opposite sides of the recess 7b. Insertion holes 8a and 8a for respectively passing the pair of photoconductive members 5 and 5 therethrough are formed through the support wall 8.
The connector housing 4 includes hollow plug-receiving chambers 4a and 4a for respectively receiving the optical connector plugs 2 and 2, and a lock arm 4c for engagement with a housing of a mating connector (not shown) is formed on a front end portion of an upper wall 4b of this connector housing, and retaining projections 4d and 4d, corresponding respectively to the retaining holes 7c and 7c, are formed on a rear end portion of the upper wall 4b. A recess 4e is formed in a central portion of the upper wall 4b, and a guide portion 4f for the ferrule holder 3 is formed in communication with the recess 4e.
In the above construction, before forming each of the optical connector plugs 2 and 2, the photoconductive member 5 is first passed through the ferrule holder 3, and then a compression coil spring (resilient member) 9 is mounted on the photoconductive member 5. As the ferrule holder 3 is connected, together with the optical connector plugs 2 and 2, to the connector housing 4, the ferrule holder 3 is guided by the guide portion 4f, and shown in FIG. 8, the retaining projections 4d and 4d (only one of which is shown in FIG. 8) on the connector housing 4 are firmly engaged respectively in the retaining holes 7c and 7c (only one of which is shown in FIG. 8) in the ferrule holder 3, thereby forming the optical connector 1 which is now ready for connection to the housing of the mating connector (not shown).
In this condition, each optical connector plug 2 has a slight play because of the resilient force of the compression coil spring 9 acting between an engagement projection 6c, formed on the outer surface of the larger-diameter portion 6b of the ferrule 6 over an entire periphery thereof, and an engagement portion 7d formed within the housing 7.
In the above prior art, before forming the optical connector plugs 2 and 2, the photoconductive members 5 and 5 must be passed through the ferrule holder 3, and therefore there has been encountered a problem that the efficiency of the operation can not be enhanced because of this cumbersome operation.
And besides, the ferrule holder 3 and the connector housing 4 are firmly engaged with each other, and therefore for example, even when it becomes necessary to effect the maintenance of the optical connector 1 or to exchange the connector housing 4, the engagement between the ferrule holder 3 and the connector housing 4 can not be easily canceled, and in some cases there is a possibility that this leads to damage to these parts.
Furthermore, since the optical connector plug 2 is formed at the end portion of the photoconductive member 5, the photoconductive member 5 can not be removed from the ferrule holder 3, which leads to a problem that the optical connector 1 can not have extensibility.